Posted by drmarkgriffiths
The last time I examined some aspect of blindness in my blog was when I examined amaurophilia, a sexual paraphilia where the individual derives sexual pleasure and arousal “by a partner who is blind or unable to see due to artificial means such as being blindfolded or having sex in total darkness”. In today’s blog I briefly examine Anton-Babinski Syndrome (ABS), a rare symptom of occipital lobe brain damage in which sufferers who are “cortically blind”, adamantly claim they are capable of seeing and/or experiencing strange hallucinatory episodes. Consequently, confabulation is common among ABS sufferers. (Confabulation is viewed as a memory disturbance characterized by verbal statements or actions that do not accurately reflect the facts and evidence. Some have described it as “honest lying” because the person usually has no intention of to deceiving the people they are talking to and are usually unaware that the things they are saying are false). For instance, Raj Patel in a 2009 book The Value of Nothing reported one female ABS patient saw a new village outside her window that she couldn’t recall being built. On another occasion she saw a girl in her house that she claimed needed food.
ABS was named after Gabriel Anton (an Austrian psychiatrist and neurologist) and Joseph Babinski (a French neurologist of Polish heritage), and is a form of anosognosia (i.e., an unawareness of severe bodily impairment or disability) that typically arises following a stroke or head injury. According to a 2009 case report by Dr. M. Maddula and colleagues in the Journal of Medical Case Reports, ischemic cerebrovascular disease is the most common etiology of cortical blindness in ABS. A literature review in a 2012 issue of the Journal of Behavioral and Brain Science notes that other diseases described as causes of cortical blindness leading to ABS are “MELAS [Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes], preeclampsia, obstetric hemorrhage, trauma, adrenloeucodistrophy, hypertensive encephalopathy and angiographic procedures”.
In the late 1890s, Anton described three patients (one denying blindness, one denying deafness, and one denying left-sided paralysis) although it was Babinski that coined the term ‘anosognosia’ in 1914 (derived from the Greek for ‘lacking knowledge about disease’). Similar cases were then published sporadically over the next 50 years including Pötzl (1924), Nielsen (1946), Hécaen and de Ajuriaguerra (1954), Levin, Povorinsky, and Tonkonogy (1961), and Hécaen (1972). Some view this condition as the conceptual opposite of blindsight. The Wikipedia entry on ABS notes that:
“The sudden development of bilateral occipital dysfunction is likely to produce transient physical and psychical effects in which mental confusion may be prominent. It may be some days before the relatives, or the nursing staff, stumble onto the fact that the patient has actually become sightless. This is not only because the patient ordinarily does not volunteer the information that he has become blind, but he furthermore misleads his entourage by behaving and talking as though he were sighted. Attention is aroused however when the patient is found to collide with pieces of furniture, to fall over objects, and to experience difficulty in finding his way around. He may try to walk through a wall or through a closed door on his way from one room to another. Suspicion is still further alerted when he begins to describe people and objects around him which, as a matter of fact, are not there at all. Thus we have the twin symptoms of anosognosia (or lack of awareness of defect) and confabulation, the latter affecting both speech and behaviour”.
According to the US National Institute of Health, ABS affects less than 200,000 people in the whole of the US population. ABS sufferers typically explain their bruises and injuries as a result of clumsiness or absentmindedness (rather than poor vision or blindness). Consequently, confabulation is often a way in which ABS can be diagnosed.
There are a number of theories as to how ABS occurs as no-one knows for sure why patients deny they are blind. One school of thought is that visual cortex damage may result in an inability to communicate with the brain’s speech-language areas (i.e., visual information is received but not interpreted correctly and a verbal response is confabulated). In fact, Dr. G. Goldenberg and colleagues in a 1995 issue of the journal Neuropsychologia claim that damage to the visual association cortex is thought to be one of the main causes explaining the loss of awareness of the visual deficit. Others postulate that ABS patients are simply having hallucinatory sensations (unrelated to their actual surrounding reality).
In a 1978 French neurology journal, Dr. J.M. Verret and Dr. J. Lapresle described a female ABS patient presenting with an accompanying delusional conviction in which she “recognised her left upper limb with the aid of her right hand, but immediately denied its existence when she viewed it directly. In contrast, when placed in front of a mirror, she recognised this upper limb perfectly, recognition disappearing again when direct vision was associated with vision in the mirror”. The authors suggested there was a possibility of a resurgence in adult life of the duality of the visual body image, direct or reflected, such as is normally experienced in childhood and, more prolonged, in identical twins.
The most recently published paper on ABS was a 2012 paper by Dr. Juan Carvajal and his colleagues in the Journal of Behavioral and Brain Science. They reported the cases of two ABS patients. The first was a 96-year-old male with visual anosognosia secondary to cerebral artery thrombosis, and the second was a 56-year-old female with ABS secondary to central nervous system angiitis in relation with multiple sclerosis and Hashimoto’s thyroiditis. They reported that although ischemic vascular cerebral disease is a frequent etiology with ABS (as noted above), they believed that this was the first report of ABS in relation to angiitis with a clear autoimmune pathogenesis. ABS can be treated with cognitive therapy although in some instances it may simply fade away over time (but most in the medical profession recommend treatment rather than just letting it fade).
Dr Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Anton, G. (1898). Über Herderkrankungen des Gehirns, welche vom Patienten selbst nicht wahrgenommen werden. Wiener klinische Wochenschrift, 11, 227–229.
Anton, G. (1899). Über die selbst wharnehmoung der herederkrankungen des gehirns durch den kranken der rindenblindheit und rindentaubheit. Archiv für Psychiatrie und Nervenkrankheiten, 32, 86–127.
Babinski, J. (1914). Contribution à l’étude des troubles mentaux dans l’hemiplegie cerebrale (anosognosie). Revue Neurologique, 27, 845–847.
Carvajal, J.J.R., Cárdenas, A.A.A, Pazmiño, G.Z., & Herrera, P.A. (2012). Visual anosognosia (Anton-Babinski Syndrome): Report of two cases associated with ischemic cerebrovascular disease. Journal of Behavioral and Brain Science, 2, 394-398.
Critchley, M. (1953). The parietal lobes. London: E. Arnold and Co.
Goldenberg, G., Mullbacher, W. & Nowak, A. (1995). Imagery without perception: A case study of anosognosia for cortical blindness. Neuropsychologia, 33, 1373-1382.
Hécaen, H. (1972). Introduction a la neuropsychologie. Paris: Larousse.
Levin, G. Z., Povorinsky, Y. A., & Tonkonogy, J. M. (1961). Analysis of the case with agnosia of faces developed after air embolism of cerebral vessels [in Russian]. In G. B. Abramovich & G. Z. Levin (Eds.), Problems of Localization and Focal Diagnostic in Neurology and Psychiatry (pp. 111-123), Leningrad: Bechterev Institute Press.
Maddula, M., Lutton, S. & Keegan, B. (2009). Anton’s Syn-drome due to cerebrovascular disease: A case report. Journal of Medical Case Reports, 3, 9028.
McGlynn, S.M. & Schacter, D.L. (1989). Unawareness of deficits in neuropsychological syndromes. Journal of Clinical and Experimental Neuropsychology, 11, 143-205.
Misra, M., Rath, S. & Mohanty, A.B. (1989). Anton Syndrome and cortical blindness due to bilateral occipital infarction. Indian Journal of Ophthalmology, 37(4), 196.
Nielsen, J. M. (1946). Agnosia, apraxia, aphasia: Their value in cerebral localization. New York: Hoeber.
Patel, R. (2009). The Value of Nothing: How to Reshape Market. London: Portobello Books.
Poetzl, O. (1924). Uber die Storungen der Selbst wahrnehmung bey linksetiger hemiplegie. Zeitschrift für Neurologie und Psychiatrie, 93, 117–168.
Verret, J.M. & Lapresle, J. (1978). [Anton-Babinski syndrome with recognition of the left upper limb on visualization in a mirror] (Article in French). Rev Neurol (Paris), 134, 709-713.
Wikipedia (2012). Anton-Babinski Syndrome. Located at: http://en.wikipedia.org/wiki/Anton–Babinski_syndrome